Rapid update actuals and forecasts

Tracking and forecasting cloud cover globally via high-resolution weather satellites.

Clouds are always changing, so why keep running with old data?

A key challenge for solar energy suppliers and their electricity markets and networks is the fact that the amount of solar radiation reaching the Earth’s surface is constantly changing. This is referred to as ‘solar intermittency’. There are two main causes of this intermittency – time of day/year and cloud cover.

The amount of solar radiation reaching a location changes as the intensity of solar irradiation changes over the course of day and night. This is very predictable and can be forecasted easily. But cloud cover and dust storms are a whole different ball game! One cloud can vary enormously from another cloud. And clouds can form, change and dissipate within hours or minutes. These fast-moving and rapidly-changing clouds require forecasting solutions that are just as speedy.

Solcast has developed the ability to measure and forecast cloud cover in order to rapidly update solar forecasts.

solar-irradiance-global-coverage-map.pngRapid Update Forecasting update cycles, globally

What does “Rapid Update” mean?

Rapid Updates means knowing the exact locations and properties of clouds affecting a solar asset, updating every 10 or 15 minutes. This includes knowledge and active tracking of cloud opacity (thickness), height, movement and tendency. Traditional weather forecasts have typically updated only a few times per day, or hourly at best. For most solar energy applications that’s not good enough.

Older forms of solar forecasting relied on Numerical Weather Prediction models as the sole meteorological input. These models are a crucial source of information when making a solar forecast for tomorrow and beyond, but they don’t actually track or predict cloud cover and are therefore missing large pieces of information affecting forecast accuracy.

How does Solcast produce Rapid Update Actuals and Forecasts?

Solcast goes all-out when it comes to Rapid Update Actuals and Forecasts and include this capability in all its products. Using five high-resolution weather satellites, Solcast generates over 600 million forecast and actuals data points every hour. Our ‘Live’ (Actuals) data and the first 4 hours of our Forecast data are updated every 10 to 15 minutes with each new satellite scan. For Utility Scale solar farm products, forecast resolution is pushed even further to provide you with 5-minute or even 1-minute resolution forecasts! The volume of data and forecasts managed by Solcast allows for the rapid generation of ensembles of individual forecasts for each time-step. This is captured as uncertainty in any given weather regime and communicated back to customers.

rapid-update-solar-forecasting-europe.gif Rapid update solar forecasting in action over the United Kingdom for 17 Match 2018. Forecasted cloud appears in the right graphic and actual observed cloud in the left graphic.

Rapid access to Rapid Update Actuals and Forecast products

You can instantly evaluate our rapid update data by signing up for the Solcast API service. Within minutes you’ll have access to trial forecasting tools with little hassle and no upfront costs.